Cause of deadly Seattle news chopper crash unknown

NTSB investigators are combing the scene of a deadly news helicopter crash near the Seattle Center. But why the tragic accident that killed two men happened, could be unknown for at least several months.

http://archive.hattiesburgamerican.com/VideoNetwork/3359085819001/Cause-of-deadly-Seattle-news-chopper-crash-unknownhttp://bc_gvpc_od-f.akamaihd.net/media/963482463001/201403/405/963482463001_3358907379001_5802fd97-eb92-47c7-b08c-bf98fcb8ae85.mp4?pubId=44854208001&videoId=3359085819001http://archive.hattiesburgamerican.com/VideoNetwork/3359085819001/Cause-of-deadly-Seattle-news-chopper-crash-unknownhttp://bc_gvpc.edgesuite.net/img/963482463001/201403/3029/963482463001_3358716275001_thumbnail-for-video-3358815312001.jpgCause of deadly Seattle news chopper crash unknownNTSB investigators are combing the scene of a deadly news helicopter crash near the Seattle Center. But why the tragic accident that killed two men happened, could be unknown for at least several months.two killedntsb investigationwhat caused chopper crashseattle news chopper crashNational Newshelicopter crash02:42